Field of the Invention
The present invention relates to a method of manufacturing an image capturing apparatus.
Description of the Related Art
There is known an arrangement in which, in an image capturing apparatus, a light waveguide is arranged above a photoelectric conversion unit arranged in an imaging region in order to increase the amount of light entering the photoelectric conversion unit. Japanese Patent Laid-Open No. 2015-144298 describes a manufacturing method of facilitating formation of a contact plug electrically connected to a wiring pattern in a peripheral region which processes a signal output from an imaging region in an image capturing apparatus including a light waveguide. Silicon nitride is deposited as a material for the light waveguide so as to cover an interlayer insulation film such that an opening portion arranged above a photoelectric conversion unit of the interlayer insulation film is embedded. Then, a step generated on the surface of the deposited silicon nitride is planarized by a Chemical Mechanical Polishing (CMP) method to form the light waveguide. After that, a portion of the light waveguide arranged in the peripheral region is removed.